I am looking for some cheap and LowWattage Hardware where I can run Processing and connect a USB device (FTDI Adapter). I am using Processing to control my Arduino via TouchOCS (iOS) with xBEE and would like to have it running 24/7. Currently I use my Laptop which I do not like to use for this.

First I was thinking of a Raspberry Pi, but it seems like that its not easy to get it running on a PI and if so, the performance is way too slow.

Is it possible to use a NAS or maybe a Linux based router using dd wrt? 

Any other options?

Thx a lot

Cheers

Thorsten